Highly-accurate stability-preserving optimization of the Zener viscoelastic model, with application to wave propagation in the presence of strong attenuation - Archive ouverte HAL Access content directly
Journal Articles Geophysical Journal International Year : 2016

Highly-accurate stability-preserving optimization of the Zener viscoelastic model, with application to wave propagation in the presence of strong attenuation

Abstract

This article concerns the numerical modeling of time-domain mechanical waves in vis-coelastic media based on a generalized Zener model. To do so, classically in the literature relaxation mechanisms are introduced, resulting in a set of so-called memory variables and thus in large computational arrays that need to be stored. A challenge is thus to accurately mimic a given attenuation law using a minimal set of relaxation mechanisms. For this purpose, we replace the classical linear approach of Emmerich & Korn (1987) with a nonlinear optimization approach with constraints of positivity. We show that this technique is significantly more accurate than the linear approach. Moreover it ensures that physically-meaningful relaxation times that always honor the constraint of decay of total energy with time are obtained. As a result these relaxation times can always be used in a stable way in a modeling algorithm, even in the case of very strong attenuation for which the classical linear approach may provide some negative and thus unusable coefficients.
Fichier principal
Vignette du fichier
Gji2.pdf (692.01 Ko) Télécharger le fichier
Origin : Files produced by the author(s)
Loading...

Dates and versions

hal-01228901 , version 1 (14-11-2015)
hal-01228901 , version 2 (18-01-2016)

Identifiers

Cite

Emilie Blanc, Dimitri Komatitsch, Emmanuel Chaljub, Bruno Lombard, Zhinan Xie. Highly-accurate stability-preserving optimization of the Zener viscoelastic model, with application to wave propagation in the presence of strong attenuation. Geophysical Journal International, 2016, 205, pp.427-439. ⟨10.1093/gji/ggw024⟩. ⟨hal-01228901v2⟩
504 View
4818 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More